Much of the black on white photographic industry depends on the use of silver salts, e.g. mixed halides, as the active agent. One characteristic of the silver process is its high photosensitivity achieved through amplification; however, this benefit is realized at some sacrifice to resolution. Further, images of high acuity and density require liquid chemical processing with inherent process limitations and environmental drawbacks. In contrast, polyacetylene-based, "processless" films are imaged solely by the application of one or more simple physical means, such as by exposure to ionizing radiation which provides instantaneous imprinting at 1000 lines/mm, or higher resolution, at a high density. Alternatively, a first simple physical means of exposure to thermal radiation can cause latent-image formation by the deactivation of the polyacetylene imaging component. The final image can then be developed by a second simple physical means of exposure to ionizing radiation. In both cases, not only does this mode of imaging reduce the time for obtaining an imaged product, but also it avoids safety and environmental problems associated with chemical development, eliminates the cost of such processing and increases the quality and efficiency of imaging.
Notwithstanding the benefits of polyacetylenic films, the majority of diacetylenic compounds which are capable of color development produce blue, purple, magenta, and red coloration; yellow being less common and pure permanent black being virtually unknown. Further complicating the issue of a chosen color development is the widely varying photosensitivity of the individual color producing diacetylenes.